Styrofoam SIS
capnkent
| Posted in Green Products and Materials on
Wondering if anyone can shed some light on Styrofoam’s SIS product? Did you use it over other sheathing? Expensive? Installation problems? Things to watch for? Did you have to engineer the walls? Which thickness did you use?
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Replies
I've used the 1" and was pretty happy with it - no special engineering on the walls and we did not install additional sheathing. It is rated as structural sheathing as long as it is nailed properly so follow the installation instructions closely. I was a little leary at first counting on it as my lateral bracing so I let in 1x4 as well just to be sure but after using it, I don't think it is really necessary. I do not like relying on taped seams as my WRB so I installed the DOW housewrap overtop of it even though they said that was not necessary.
Only issue was we had to order full pallets of it - 20something sheets each and had to wait a few weeks for it to show up. Was around $22 for an 8' sheet. Starting another house and going to use it again.
Kent,
You can read a GBA review of the product (SIS) on page 11 of issue number 5 of the Insider newsletter: Insider No. 5.